Clarence Dutton started the tradition of naming geographical features in the Grand Canyon after mythological deities and heroic figures.[5] Guinevere Castle was named by cartographerRichard Tranter Evans (1881–1966), after Guinevere, queen and wife of King Arthur, in keeping with an Arthurian naming theme for other geographical features in the vicinity, e.g. King Arthur Castle, Elaine Castle, Excalibur, Gawain Abyss, Bedivere Point, Lancelot Point, Holy Grail Temple, and Galahad Point.[6] This feature's name was officially adopted in 1908 by the U.S. Board on Geographic Names.[2]Harvey Butchart climbed both King Arthur Castle and Guinevere Castle on August 25, 1965, placing the first cairn on Guinevere, but was not the first person there as he found evidence that Native Americans had been there, namely a shelter and a granary.[7][8] King Arthur and Guinevere became the 34th and 35th of the 83 summits Butchart would climb in the Grand Canyon.[7]
Geology
The summit is composed of PermianKaibab Limestone and cream-colored Permian Coconino Sandstone. This sandstone, which is the third-youngest stratum in the Grand Canyon, was deposited 265 million years ago as sand dunes. Below the Coconino Sandstone is reddish slope-forming, Permian Hermit Formation, which in turn overlays the Pennsylvanian-Permian Supai Group. Further down are strata of the cliff-forming MississippianRedwall Limestone, and slope-forming CambrianTonto Group.[9] Precipitation runoff from Guinevere Castle drains west to the Colorado River via Shinumo Creek.
^John Annerino, Hiking the Grand Canyon, 2017, Simon & Schuster, ISBN9781510714984, page 73.
^Peel, M. C.; Finlayson, B. L.; McMahon, T. A. (2007). "Updated world map of the Köppen−Geiger climate classification". Hydrol. Earth Syst. Sci. 11. ISSN1027-5606.
^Randy Moore and Kara Felicia Witt, The Grand Canyon: An Encyclopedia of Geography, History, and Culture, 2018, ABC-CLIO Publisher, page 151.
^Gregory McNamee, Grand Canyon Place Names, 1997, Mountaineers Publisher, ISBN9780898865332, page 58.